Miscarriage matters: the epidemiological, physical, psychological, and economic costs of early pregnancy loss.

Miscarriage is generally defined as the loss of a pregnancy before viability. An estimated 23 million miscarriages occur every year worldwide, translating to 44 pregnancy losses each minute. The pooled risk of miscarriage is 15·3% (95% CI 12·5-18·7%) of all recognised pregnancies. The population prevalence of women who have had one miscarriage is 10·8% (10·3-11·4%), two miscarriages is 1·9% (1·8-2·1%), and three or more miscarriages is 0·7% (0·5-0·8%). Risk factors for miscarriage include very young or older female age (younger than 20 years and older than 35 years), older male age (older than 40 years), very low or very high body-mass index, Black ethnicity, previous miscarriages, smoking, alcohol, stress, working night shifts, air pollution, and exposure to pesticides. The consequences of miscarriage are both physical, such as bleeding or infection, and psychological. Psychological consequences include increases in the risk of anxiety, depression, post-traumatic stress disorder, and suicide. Miscarriage, and especially recurrent miscarriage, is also a sentinel risk marker for obstetric complications, including preterm birth, fetal growth restriction, placental abruption, and stillbirth in future pregnancies, and a predictor of longer-term health problems, such as cardiovascular disease and venous thromboembolism. The costs of miscarriage affect individuals, health-care systems, and society. The short-term national economic cost of miscarriage is estimated to be £471 million per year in the UK. As recurrent miscarriage is a sentinel marker for various obstetric risks in future pregnancies, women should receive care in preconception and obstetric clinics specialising in patients at high risk. As psychological morbidity is common after pregnancy loss, effective screening instruments and treatment options for mental health consequences of miscarriage need to be available. We recommend that miscarriage data are gathered and reported to facilitate comparison of rates among countries, to accelerate research, and to improve patient care and policy development.

Gonadotropin-releasing hormone agonist downregulation combined with hormone replacement therapy improves the reproductive outcome in frozen-thawed embryo transfer cycles for patients of advanced reproductive age with idiopathic recurrent implantation failure.

BACKGROUND: To determine whether gonadotropin-releasing hormone (GnRH) agonist downregulation combined with hormone replacement therapy (HRT) can improve the reproductive outcomes in frozen-thawed embryo transfer cycles for older patients (aged 36-43 years) with idiopathic recurrent implantation failure (RIF). METHODS: This retrospective cohort study involved 549 older patients undergoing their third cleavage-stage embryo or blastocyst transfer over a 5-year period (January 2015-December 2020) at Northwest Women's and Children's Hospital after in vitro fertilization/intracytoplasmic sperm injection cycles. Patients with known endometriosis or adenomyosis were excluded from the study. The patients were divided into three groups according to the endometrial preparation protocol: the natural cycle (NC) group (n = 65), the HRT group (n = 194), and the GnRH agonist downregulation combined with HRT cycle (GnRH agonist-HRT) group (n = 290). The primary outcome was the live birth rate, and the secondary outcomes were the clinical pregnancy, miscarriage, and ongoing pregnancy rates. RESULTS: The live birth rate in the GnRH agonist-HRT group (36.55%) was higher than that in the HRT group (22.16%) and NC group (16.92%) (P < 0.0001). Similarly, a logistic regression model adjusting for potential confounders showed that the live birth rate was higher in the GnRH agonist-HRT group than in the HRT group (odds ratio, 0.594; 95% confidence interval, 0.381-0.926; P = 0.021) and NC group (odds ratio, 0.380; 95% confidence interval, 0.181-0.796; P = 0.010). CONCLUSIONS: The GnRH agonist-HRT protocol improves the live birth rate in frozen-thawed embryo transfer cycles for patients of advanced reproductive age with RIF. We hypothesize that the GnRH agonist-HRT protocol enhances implantation-related factors and promotes optimal endometrial receptivity, leading to an improved live birth rate. These findings are also useful for further investigating the underlying mechanism of the GnRH agonist-HRT protocol in improving the reproductive outcomes for patients of advanced reproductive age with RIF. TRIAL REGISTRATION: This research protocol was approved by the hospital institutional ethics committee (No. 2021002).

Preconceptional evaluation of women with recurrent pregnancy loss: the additional value of assessing vascular and metabolic status.

BACKGROUND: A majority of recurrent pregnancy loss cases (RPL) remains unexplained. We hypothesized that complications in vascular and metabolic status may guide towards underlying problems that also predispose to RPL and that the number of pregnancy losses is related. METHODS: A retrospective study in 123 women with either a history of low-order RPL (2-3 pregnancy losses) or high-order RPL (≥ 4 pregnancy losses) and 20 women with a history of uncomplicated pregnancy (controls) was performed. Vascular status was assessed by measuring hemodynamic parameters, determining abnormal parameters and analyzing their contribution to the circulatory risk profile (CRP). In a similar way, metabolic status was assessed. Metabolic parameters were measured, used to determine abnormal parameters and analyzed for their contribution to the metabolic syndrome (MetS). RESULTS: No major differences were observed in vascular or metabolic parameters between women with RPL and controls. There was no relation with the number of pregnancy losses. However, when analyzing the presence of abnormal constituents, more than 80% of women with RPL had at least one abnormal constituent of the CRP. While only 27% had one or more abnormal constituent of the MetS. CONCLUSIONS: The presence of abnormal circulatory factors prior to pregnancy, and to lesser extent constituents of the metabolic syndrome, may predispose to RPL and offer new insights to its pathophysiology.

Proteomic and functional analysis of proteins related to embryonic development of decidua in patients with recurrent pregnancy loss†.

Recurrent pregnancy loss (RPL) is defined as the loss of two or more consecutive pregnancies before the 20 weeks of gestation. RPL affects about 1-2% of couples trying to conceive; however, the mechanisms leading to this complication are largely unknown. Our previous studies using comparative proteomics identified 314 differentially expressed proteins (DEPs) in the placental villous. In this study, we identified 5479 proteins from a total of 34 157 peptides in decidua of patients with early RPL (data are available via ProteomeXchange with identifier PXD023849). Further analysis identified 311 DEPs in the decidua tissue; and 159 proteins were highly expressed, whereas 152 proteins were lowly expressed. These 311 proteins were further analyzed by using Ingenuity Pathway Analysis. The results suggested that 50 DEPs played important roles in the embryonic development. Upstream analysis of these DEPs revealed that angiotensinogen was the most important upstream regulator. Furthermore, protein-protein interaction analysis of the embryonic development DEPs from the placental villous and decidua was performed in the STRING database. This study identified several proteins specifically associated with embryonic development in decidua of patients with early RPL. Therefore, these results provide new insights into potential biological mechanisms, which may ultimately inform RPL.

LncRNA LINC01088 inhibits the function of trophoblast cells, activates the MAPK-signaling pathway and associates with recurrent pregnancy loss.

Long noncoding RNAs (lncRNAs) have been reported to be involved in various cellular processes and to participate in a variety of human diseases. Recently, increasing studies have reported that lncRNAs are related to many reproductive diseases, such as pathogenesis of recurrent pregnancy loss (RPL), preeclampsia (PE) and gestational diabetes mellitus (GDM). In this study, we aimed to investigate the effect of LINC01088 in trophoblast cells and its potential role in pathogenesis of RPL. LINC01088 was found to be upregulated in first-trimester chorionic villi tissues from RPL patients. Increased LINC01088 repressed proliferation, migration and invasion of trophoblast cells, and promoted apoptosis of trophoblast cells. Further exploration indicated that LINC01088 decreased the production of nitric oxide (NO) by binding and increasing Arginase-1 and decreasing eNOS protein levels. Importantly, JNK and p38 MAPK-signaling pathways were active after overexpression of LINC01088. In conclusion, our studies demonstrated that LINC01088 plays an important role in the pathogenesis of RPL, and is a potential therapeutic target for the treatment of RPL.

Severe metabolic disorders coexisting with Werner syndrome: a case report.

Werner syndrome, also called adult progeria, is a heritable autosomal recessive human disorder characterized by the premature onset of numerous age-related diseases including juvenile cataracts, dyslipidemia, diabetes mellitus (DM), osteoporosis, atherosclerosis, and cancer. Werner syndrome is a segmental progeroid syndrome whose presentation resembles accelerated aging. The most common causes of death for WS patients are atherosclerosis and cancer. A 40-year-old female presented with short stature, bird-like facies, canities with alopecia, scleroderma-like skin changes, and non-healing foot ulcers. The patient reported a history of delayed puberty, abortion, hypertriglyceridemia, and juvenile cataracts. A clinical diagnosis of WS was made and subsequently confirmed. We discovered two WRN gene mutations in the patient, Variant 1 was the most common WRN mutation, nonsense mutation (c.1105C>T:p.R369Ter) in exon 9, which caused a premature termination codon (PTC) at position 369. Variant 2 was a frameshift mutation (c.1134delA:p.E379KfsTer5) in exon 9, which caused a PTC at position 383 and has no published reports describing. Patients with WS can show a wide variety of clinical and biological manifestations in endocrine-metabolic systems (DM, thyroid dysfunction, and hyperlipidemia). Doctors must be cognizant of early manifestations of WS and treatment options.

Abnormal uterine inflammation in obstetric syndromes: molecular insights into the role of chemokine decoy receptor D6 and inflammasome NLRP3.

The adaptation of the uterine environment into a favorable immunological and inflammatory milieu is a physiological process needed in normal pregnancy. A uterine hyperinflammatory state, whether idiopathic or secondary to hormonal or organic uterine disorders (polycystic ovary syndromes, endometriosis/adenomyosis and fibroids), negatively influences the interactions between decidua and trophoblast, early in gestation, and between chorion and decidua later in pregnancy. Abnormal activation of uterine inflammatory pathways not only contributes to the pathogenesis of the obstetric syndromes, i.e. recurrent pregnancy loss (RPL), pre-term delivery (PTD) and pre-eclampsia (PE), but also to correlates with severity. In this review, we summarize recent advances in the knowledge of uterine molecular mechanisms of inflammatory modulation in normal pregnancy and obstetric syndromes (RPL, PTD and PE). In particular, we focus on two regulators of uterine/placental inflammation: the NLRP3 inflammasome and the chemokines decoy receptor D6. We performed comprehensive review of the literature in PubMed and Google Scholar databases from 1994 to 2018. The available evidence suggests that: (i) the expression of inflammasome NLRP3 is increased in the endometrium of women with unexplained RPL, in the chorioamniotic membranes of women with PTL and in the placenta of women with PE; (ii) there is a role for abnormal expression and function of D6 decoy receptor at the feto-maternal interface in cases of RPL and PTD and (iii) the function of placental D6 decoy receptor is impaired in PE. A wider comprehension of the inflammatory molecular mechanisms involved in the pathogenesis of the obstetric syndromes might lead to the identification of new potential therapeutic targets.

Assessing endometrial receptivity after recurrent implantation failure: a prospective controlled cohort study.

RESEARCH QUESTION: What is the prevalence of disrupted markers of endometrial function among women experiencing recurrent implantation failure (RIF), and does the prevalence differ from a control cohort? DESIGN: Prospective controlled cohort study. In total, 86 women with a history of RIF and 37 women starting their first fertility treatment were recruited for this study. Endometrial and blood profiling were carried out in a hormone-substituted cycle using oestradiol and progesterone. Endometrial biopsies were analysed by histology, immune cell profiling, and the endometrial receptivity array (ERA®) test (Igenomix, Valencia, Spain). The vaginal microbiome was analysed using a NGS-based technology (ArtPRED, Amsterdam, the Netherlands). Blood tests included oestradiol, progesterone, prolactin, thyroid-stimulating hormone, vitamin D and anti-phospholipid antibody levels. RESULTS: Patients who had experienced RIF produced a range of test abnormalities. Compared with controls, women with RIF had a higher prevalence of chronic endometritis (24% versus 6%), a lower vitamin D level and a borderline lower progesterone level. Women who had experienced RIF had a more favourable vaginal microbiome compared with controls. Although the RIF cohort was older than the controls (mean age 33.8 years versus 30.2 years), no differences between the groups were observed in immune cell profiling and the ERA test. CONCLUSION: These data demonstrate that a single test or treatment for the endometrial factor in RIF is unlikely to be clinically effective. Diagnosing the endometrium in women with RIF permits targeted rather than blind interventions. Relative vitamin D deficiency, lower mid-luteal progesterone and chronic endometritis are ready targets for treatment. Understanding the role and treatment of an unfavourable vaginal microbiome in RIF needs further investigation.

Family history and risk of miscarriage: A systematic review and meta-analysis of observational studies.

INTRODUCTION: Miscarriage, a spontaneous pregnancy loss at <24 weeks' gestation, is a common complication of pregnancy but the etiologies of miscarriage and recurrent miscarriage are not fully understood. Other obstetric conditions such as preeclampsia and preterm birth, which may share similar pathophysiology to miscarriage, exhibit familial patterns, suggesting inherited predisposition to these conditions. Parental genetic polymorphisms have been associated with unexplained miscarriage, suggesting there could be a genetically inherited predisposition to miscarriage. This systematic review and meta-analysis of observational studies aimed to assess the association between family history of miscarriage and the risk of miscarriage in women. MATERIAL AND METHODS: A systematic review and meta-analysis of observational studies was carried out in accordance with Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. Electronic searches using databases (MEDLINE, EMBASE and CINAHL) were carried out to identify eligible studies from 1946 until 2019. Observational studies (cohort or case-control) were included. Human studies only were included. Participants were women of reproductive age. Exposure was a family history of one or more miscarriage(s). The primary outcome was miscarriage in women. Abstracts were screened and data were extracted by two independent reviewers. Study quality was assessed using Critical Appraisal Skills Program (CASP) tools. Data were pooled from individual studies using the Mantel-Haenszel method to produce pooled odds ratios (ORs) with 95% confidence intervals (95% CI). Systematic review registration number (PROSPERO): CRD42019127950. RESULTS: Thirteen studies were identified in the systematic review; 10 were eligible for inclusion in the meta-analysis. Twelve studies reported an association between family history of miscarriage and miscarriage in women. In all, 41 287 women were included in the meta-analysis. Women who miscarried were more likely to report a family history of miscarriage (pooled unadjusted OR 1.90, 95% CI 1.37-2.63). Overall study quality and size varied, with few adjusting for confounding factors. Results should be interpreted with caution as the associations presented are based on unadjusted analyses only. CONCLUSIONS: Women who miscarry may be more likely to have a family history of miscarriage. Further research is required to confirm or refute the findings.

The AGT Haplotype of the ESR2 Gene Containing the Polymorphisms rs2077647A, rs4986938G, and rs1256049T Increases the Susceptibility of Unexplained Recurrent Spontaneous Abortion in Women in the Chinese Hui Population.

BACKGROUND Estrogen has an important role in unexplained recurrent spontaneous abortion (URSA). Polymorphisms of the ESR1 gene and the ESR2 gene have been identified as risk factors for URSA, but with varied associations in Chinese populations. This study aimed to compare the role of gene polymorphisms of ESR1 and ESR2 and the risk of URSA in the Chinese Hui and Chinese Han populations. MATERIAL AND METHODS Chinese Hui women (n=171) and Chinese Han women (n=234) with URSA were compared with healthy controls (n=417) matched by ethnicity and age. Genotyping was performed using direct sequencing and identified three polymorphisms of the ESR1 gene (rs9340799, rs2234693, and rs3798759) and three polymorphisms of the ESR2 gene (rs207764, rs4986938, and rs1256049). The association between ESR1 and ESR2 gene polymorphisms and the risk of URSA was evaluated statistically using the odds ratio (OR) and 95% confidence interval (CI). RESULTS No association was detected between the allelic, dominant, and recessive models of ESR1 and ESR2 gene polymorphisms and the risk of URSA in Chinese Han and Hui populations (p>0.05). The distribution of the AGT haplotype containing ESR2 gene polymorphisms rs2077647A, rs4986938G, and rs1256049T was significantly reduced in patients with URSA compared with controls in the Chinese Hui population (OR, 0.29; 95% CI, 0.14-0.62; p=0.0009; padj=0.005). CONCLUSIONS The AGT haplotype of the ESR2 gene containing the polymorphism rs2077647A, rs4986938G, and rs1256049T (ESR2 hapAGT) was a protective factor for URSA in women in the Chinese Hui population when compared with the Chinese Han population.

Intravenous immunoglobulin G treatment increases live birth rate in women with recurrent miscarriage and modulates regulatory and exhausted regulatory T cells frequency and function.

Exhausted T cells and regulatory T (Treg) cells have been recently proposed to be new risk factors for recurrent miscarriage (RM). Intravenous immunoglobulin G (IVIG) treatment reported to modulate various immune cells. In this study, the effects of IVIG on the frequency and function of exhausted T cells, exhausted Tregs, and Treg cells, as well as pregnancy outcome in women with unexplained RM (URM), were investigated. Ninety-four pregnant women with RM were enrolled. At the time of positive pregnancy, blood samples were drawn. Forty-four patients with URM were included as IVIG receiving treated group and received 400 mg/kg of IVIG and the rest fifty patients were considered as a control group and received no IVIG administration. IVIG was given intravenously every 4 weeks during 32 weeks of gestation. Blood samples of patients were collected after the latest administration. Exhausted T cells, exhausted Tregs, and Treg cells were evaluated pre- and posttreatment in both groups. IVIG induced a significant decrease in the frequency of exhausted Tregs population and function as well as a significant increase in Treg cells population, however, IVIG failed to affect population and the function of exhausted T cells. Pregnancy outcome was successful in IVIG treated women (86.3%) and were significantly different (P = 0.0006) in compared with the untreated URM subjects (42%). Therefore, employing of IVIG increases Treg cells and diminishes exhausted Tregs responses in RM patients with cellular immune anomalies throughout the pregnancy. Immunemodulatory effects of IVIG are probably associated with successful pregnancy outcome.

The pathophysiology of the septate uterus: a systematic review.

BACKGROUND: Little is known about the pathophysiology underlying the increased risk for impaired reproductive outcomes in women with a septate uterus. OBJECTIVES: We explored the available evidence on the pathophysiology of the septate uterus in an attempt to find a biological basis for these effects. SEARCH STRATEGY: We performed a systematic literature search in OVID MEDLINE and OVID EMBASE from inception to January 2018. SELECTION CRITERIA: We selected studies that investigated the pathophysiology of the septate uterus. Case reports or reviews without original data were excluded. DATA COLLECTION AND ANALYSIS: Two reviewers independently evaluated potentially eligible papers. MAIN RESULTS: Thirty-eight studies were included for analysis. The overall findings were that the intrauterine septum consists of endometrium and myometrium similar to the uterine wall. All five imaging studies that evaluated vascularity found that most of the intrauterine septa were vascularised. Histological studies found that the intrauterine septum consisted of myometrium and was covered by endometrium (n = 9). The endometrium covering the septum showed differences in histological composition in four studies and in gene expression in three studies compared with the normal uterine wall. CONCLUSIONS: We found no clear biological basis for the impaired reproductive outcomes in women with a septate uterus. Either the gross anatomy of the septum itself or differences in histology or gene expression of the septum could account for the increased risk of reproductive waste observed after implantation in the septum. TWEETABLE ABSTRACT: In women with a septate uterus differences in histology or gene expression could account for impaired reproductive outcome.

Improved in vitro fertilization success and pregnancy outcome with autologous platelet-rich plasma treatment in unexplained infertility patients that had repeated implantation failure history.

Repeated implantation failure (RIF) due to suboptimal endometrial lining is a major challenge in reproductive medicine. The study aims to evaluate effect of intrauterine platelet-rich plasma (PRP) treatment on frozen-thawed embryo transfer (FET) cycles in patients whose endometrium was unable to achieve optimal lining in unexplained infertility patients with history of RIF. We retrospectively analyzed the charts of a total of 302 cycles performed in 273 patients attending Diyar Life ART Centre between January 2014 and January 2017. After excluding 232 cycles, we compared pregnancy outcomes of 34 patients who had suboptimal endometrial lining and underwent PRP + FET and 36 patients who had optimal endometrial lining and underwent only FET. We observed that, endometrial thickness was higher after 48 hours from PRP when compared to endometrial thickness before PRP (10 mm vs. 6.25 mm, p < .001). Clinical pregnancy rate, and importantly live birth rate were also significantly higher in PRP group than the control group. Based on this information, we showed that intrauterine autologous PRP infusion is a safe, inexpensive adjuvant treatment for optimizing endometrium especially in patients with RIF history and intrauterine PRP infusion improved not only endometrial lining but also in vitro fertilization success and pregnancy outcome.

Chromosomal abnormalities in couples with recurrent spontaneous miscarriage: a 21-year retrospective study, a report of a novel insertion, and a literature review.

PURPOSE: The aim of this study is to evaluate the frequency and nature of chromosomal abnormalities in Moroccan couples with recurrent spontaneous miscarriage (RSM). In addition, the data were compared with those reported elsewhere in order to give a global estimation of chromosomal abnormalities frequencies. METHODS: The study was performed for all couples with RSM who were referred to the cytogenetic department, Pasteur Institute of Morocco, from different hospitals in Morocco between 1996 and 2016. Cytogenetic analysis was performed according to the standard method. RESULTS: Among 627 couples with RSM, the chromosomal abnormalities were identified in 11.00% of couples, with chromosomal inversions in 4.30%, reciprocal translocations in 2.71%, Robertsonian translocations in 1.43%, and deletion, isochromosome, and insertion in 0.15% each. The insertion identified [46,XX,ins(6)(p24q21q27)] is new, and is the fourth reported in association with RSM. The mosaic karyotypes were observed in 0.64%, polymorphic variants were identified in 1.27%, and numerical aneuploidy was observed in 0.15%. In regrouping our results with those in 27 other studies already published in 21 different countries, we obtained the frequency of chromosomal abnormalities in couple with RSM to be 5.16% (991/19197 couples). The reciprocal translocation was the most frequent with 2.50%, followed by Robertsonian translocation 0.83% and inversions 0.77%. The other types of chromosomal abnormalities were present with 0.98% in the world. CONCLUSION: This data showed that the frequency of chromosomal abnormalities in Moroccan couples with RSM is 11.00%, and in regrouping our results with other studies, the frequency changes to 5.16%.

Increased HLA-G Expression in Term Placenta of Women with a History of Recurrent Miscarriage Despite Their Genetic Predisposition to Decreased HLA-G Levels.

Human leukocyte antigen (HLA)-G is an immune modulating molecule that is present on fetal extravillous trophoblasts at the fetal-maternal interface. Single nucleotide polymorphisms (SNPs) in the 3 prime untranslated region (3'UTR) of the HLA-G gene can affect the level of HLA-G expression, which may be altered in women with recurrent miscarriages (RM). This case-control study included 23 women with a medical history of three or more consecutive miscarriages who delivered a child after uncomplicated pregnancy, and 46 controls with uncomplicated pregnancy. Genomic DNA was isolated to sequence the 3'UTR of HLA-G. Tissue from term placentas was processed to quantify the HLA-G protein and mRNA levels. The women with a history of RM had a lower frequency of the HLA-G 3'UTR 14-bp del/del genotype as compared to controls (Odds ratio (OR) 0.28; p = 0.039), which has previously been related to higher soluble HLA-G levels. Yet, HLA-G protein (OR 6.67; p = 0.006) and mRNA (OR 6.33; p = 0.010) expression was increased in term placentas of women with a history of RM as compared to controls. In conclusion, during a successful pregnancy, HLA-G expression is elevated in term placentas from women with a history of RM as compared to controls, despite a genetic predisposition that is associated with decreased HLA-G levels. These findings suggest that HLA-G upregulation could be a compensatory mechanism in the occurrence of RM to achieve an ongoing pregnancy.

A prospective study of physical activity and fecundability in women with a history of pregnancy loss.

STUDY QUESTION: Is physical activity (PA) associated with fecundability in women with a history of prior pregnancy loss? SUMMARY ANSWER: Higher fecundability was related to walking among overweight/obese women and to vigorous PA in women overall. WHAT IS KNOWN ALREADY: PA may influence fecundability through altered endocrine function. Studies evaluating this association have primarily utilized Internet-based recruitment and self-report for pregnancy assessment and have yielded conflicting results. STUDY DESIGN, SIZE, DURATION: This is a secondary analysis of the Effects of Aspirin in Gestation and Reproduction (EAGeR) trial (2007-2011), a multisite, randomized controlled trial of preconception-initiated low-dose aspirin. PARTICIPANTS/MATERIALS, SETTING, METHODS: Healthy women (n = 1214), aged 18-40 and with 1-2 prior pregnancy losses, were recruited from four US medical centers. Participants were followed for up to six menstrual cycles while attempting pregnancy and through pregnancy for those who became pregnant. Time to hCG detected pregnancy was assessed using discrete-time Cox proportional hazard models to estimate fecundability odds ratios (FOR) adjusted for covariates, accounting for left truncation and right censoring. MAIN RESULTS AND THE ROLE OF CHANCE: The association of walking with fecundability varied significantly by BMI (P-interaction = 0.01). Among overweight/obese women, walking ≥10 min at a time was related to improved fecundability (FOR = 1.82, 95% CI: 1.19, 2.77). In adjusted models, women reporting >4 h/wk of vigorous activity had significantly higher fecundability (FOR = 1.69, 95% CI: 1.24, 2.31) compared to no vigorous activity. Associations of vigorous activity with fecundability were not significantly different by BMI (P-interaction = 0.9). Moderate activity, sitting, and International Physical Activity Questionnaire (IPAQ) categories were not associated with fecundability overall or in BMI-stratified analyses. LIMITATIONS, REASONS FOR CAUTION: Some misclassification of PA levels as determined by the short form of the IPAQ is likely to have occurred, and may have led to non-differential misclassification of exposure in our study. Information on diet and change in BMI was not collected and may have contributed to some residual confounding in our results. The generalizability of our results may be limited as our population consisted of women with a history of one or two pregnancy losses. WIDER IMPLICATIONS OF THE FINDINGS: These findings provide positive evidence for the benefits of PA in women attempting pregnancy, especially for walking among those with higher BMI. Further study is necessary to clarify possible mechanisms through which walking and vigorous activity might affect time-to-pregnancy. STUDY FUNDING/COMPETING INTEREST(S): This work was funded by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development. The authors report no conflicts of interest in this work. TRIAL REGISTRATION NUMBER: #NCT00467363.

Angiogenesis and oxidative stress-related gene variants in recurrent pregnancy loss.

Recurrent pregnancy loss (RPL) affects ~3-5% of couples attempting to conceive and in around 50% of cases the aetiology remains unknown. Adequate vascularisation and placental circulation are indispensable for the development of a normal pregnancy. Prostaglandin-endoperoxide synthase 2 (PTGS2), vascular endothelial growth factor (VEGF) and the nitric oxide (NO) systems play important roles in reproductive physiology, participating in several steps including implantation and apoptosis of trophoblast cells. In this study we evaluated genetic polymorphisms in the inducible nitric oxide synthase (NOS2), PTGS2 and VEGFA genes as susceptibility factors for RPL. A case-control study was conducted in 149 women having two or more miscarriages and 208 controls. Allele and genotype distributions of the polymorphisms studied in the two groups were not statistically different. However, the dominant model showed that the presence of variant T (TT/GT) of rs2779249 (-1290G>T) of NOS2 was significantly associated with RPL (OR=1.58, CI 95%=1.03-2.44; P=0.037). The increased risk remained significant when adjusted for number of pregnancies, alcohol consumption and ethnicity (OR=1.92, CI95%=1.18-3.11; P=0.008). These results suggest that the variant genotypes of the functional polymorphism rs2779249 in the NOS2 promoter are a potential risk for RPL, possibly due to oxidative stress mechanisms.

Pregnancy before recurrent pregnancy loss more often complicated by post-term birth and perinatal death.

INTRODUCTION: The cause of recurrent pregnancy loss often remains unknown. Possibly, pathophysiological pathways are shared with other pregnancy complications. MATERIAL AND METHODS: All women with secondary recurrent pregnancy loss (SRPL) visiting Leiden University Medical Center (January 2000-2015) were included in this retrospective cohort to assess whether women with SRPL have a more complicated first pregnancy compared with control women. SRPL was defined as three or more consecutive pregnancy losses before 22 weeks of gestation, with a previous birth. The control group consisted of all Dutch nullipara delivering a singleton (January 2000-2015). Information was obtained from the Dutch Perinatal Registry. Outcomes were preeclampsia, preterm birth, post-term birth, intrauterine growth restriction, breach position, induction of labor, cesarean section, congenital abnormalities, perinatal death and severe hemorrhage in the first ongoing pregnancy. Subgroup analyses were performed for women with idiopathic SRPL and for women ≤35 years. RESULTS: In all, 172 women with SRPL and 1 196 178 control women were included. Women with SRPL were older and had a higher body mass index; 29.7 years vs. 28.8 years and 25.1 kg/m2 vs. 24.1 kg/m2 , respectively. Women with SRPL more often had a post-term birth (OR 1.86, 95% CI 1.10-3.17) and more perinatal deaths occurred in women with SRPL compared with the control group (OR 5.03, 95% CI 2.48-10.2). Similar results were found in both subgroup analyses. CONCLUSIONS: The first ongoing pregnancy of women with (idiopathic) SRPL is more often complicated by post-term birth and perinatal death. Revealing possible links between SRPL and these pregnancy complications might lead to a better understanding of underlying pathophysiology.

Prevalent genotypes of methylenetetrahydrofolate reductase (MTHFR) in recurrent miscarriage and recurrent implantation failure.

OBJECTIVE: To evaluate the association of two common methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms with recurrent miscarriage (RM) and repeated implantation failure (RIF) METHODS: The study comprised of 521 patients, with a history of RM (n = 370) or RIF (n = 151). One hundred forty-four women with fallopian tube blockages who had successfully conceived after the first in vitro fertilization embryo transfer treatment served as the control group. The MTHFR alleles, genotypes, and haplotypes were assessed in different groups. RESULTS: There was no difference in allele frequency and distribution of MTHFR polymorphisms between case and control patients. The 1298AA genotype was represented in a higher frequency, and 1298AC genotype was significantly lower in subfertile group when compared to the control group. A significant relationship was found between the 1298AC genotype and the RIF subgroup. The haplotype 677CC/1298AA was overrepresented in the RM subgroup (> 2 times) and haplotype 677CC/1298AC was underrepresented in the RIF subgroup (P < 0.05). Nevertheless, these two haplotypes were not connected to fertilization and embryo cleavage rates. CONCLUSION: Our findings indicate that the MTHFR gene polymorphism might play a role in the etiology of patients with RM or RIF. No adverse effects of different MTHFR haplotypes on embryo development were detected. Further studies on the biological role are needed to better understand the susceptibility to pregnancy complications.

Embryoscopy and karyotype findings of repeated miscarriages in recurrent pregnancy loss and spontaneous pregnancy loss.

PURPOSE: The aim of the study was to assess cytogenetic and embryoscopic characteristics in subsequent miscarriages of spontaneous pregnancy losses (SPL) and recurrent pregnancy losses (RPL). METHODS: A retrospective cohort of 75 women was affected by repeated pregnancy loss. Of those, 34 had SPL, 24 primary RPL, and 17 secondary RPL. Ploidy status and morphology was analyzed by transcervical embryoscopic examination of the embryo and cytogenetic analysis of the chorionic villi in subsequent miscarriages. RESULTS: Similar rates of recurrent ploidy status were observed between first and second miscarriage in SPL and RPL (82.4% recurrent ploidy status in SPL, p > 0.999; 73% recurrent ploidy status in RPL, p = 0.227). No difference was found regarding recurrent abnormal morphology between SPL and RPL (p = 0.092). However, secondary RPL resulted significantly more often in recurrent abnormal morphology compared to primary RPL (p = 0.004). CONCLUSIONS: High rates of recurrent normal/abnormal karyotypes were observed in all groups with a majority of embryos presenting with recurrent abnormal morphology. Secondary RPL presented significantly more often with recurrent abnormal morphology compared to primary RPL. These findings offer prognostic information for the affected patient and might impact treatment choice.